AR barrel wrench, piece of leather, aluminum vise jaws, Heavy bench vise, dead-blow hammer with plastic striking surface, anti-seize, headspace gouges (go, no-go), assorted feeler gauge shims for setting proper headspace according to manufacture specs.... Uhhh. I think thats about it.
Make rifle safe. Disassemble rifffle, but barrel in leather, clamp in vise, place AR wrench on barrel nut, whack that fucker (wrench) with the dead blow at least 10-12" from the barrel nut.....
If action and barrel rotate whilst whacking, clamp tighter.... Proceed with aforementioned whacking...
Once barrel nut is loose, you good. Remove barrel. Coat barrel threads in anti-seize lightly, or you favorite barrel grease (I use Militec-1 and a tie bit of anti-seize).
Place barrel nut on new barrel and spin until it bottoms out on the barrel flange.
Spin new barrel into action, or spin action onto barrel if barrel is clamped in vise. Whatever floats your boat.
Once close, put bolt into action, put "go" headspace gauge under extractor. Run bolt with gauge and close the bolt down....
Per may barrel manufacturer I used (Proof research) the recommended I place a .003" piece of shim between the bolt face and headspace gauge. And I did. You will feel when you have the headspace tight enough as you are tightening on the barrel on to the headspace gauge. Preliminarily tighten down the barrel nut and insert the no-go gauge. As long as it does not close on the no-go gauge you are all set to reassemble. Whack the barrel wrench a couple times with the dead blow hammer and you should have applied at least 50 or 60 foot pounds of torque to the barrel nut. Or you can be fancy and use a torque wrench.
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